是…的 focus construction
B1 「是…的」句 40 / 56
In short
是……的 is how Chinese zooms in on one circumstance - the time, place, manner or doer - of an action both speakers already know happened. The event is old news; 是 (shì) sits right before the highlighted piece and 的 (de) closes the sentence: 我是昨天来的 (Wǒ shì zuótiān lái de) - “it was yesterday that I came.”
The rule
Use 是……的 when an action is already established as done and you want to spotlight one of its circumstances - when, where, how, or by whom it happened. It does not announce that something happened (that is the job of 了); it takes a known event and pins down a detail of it. Compare: 我来了 (Wǒ lái le, I’ve come - the arrival is the news) versus 我是昨天来的 (Wǒ shì zuótiān lái de, it was yesterday that I came - the arrival is a given, the time is the point).
The frame is:
Subject + 是 + [focused element] + Verb + 的
Step 1 - Put 是 directly in front of the highlighted piece. Whatever you want to focus - a time word, a place phrase, a means, an agent - place 是 immediately before it: 我是昨天来的 (time), 他是坐飞机来的 (manner), 我是在北京出生的 (place). 是 does not go in front of the verb; it goes in front of the focus.
Step 2 - Close the sentence with 的. The 的 comes after the verb - and after any resultative or directional complement the verb carries, because 的 closes the whole predicate: 我是上午走进来的 (wǒ shì shàngwǔ zǒu jìnlái de), 门是风吹开的 (mén shì fēng chuīkāi de), never 我是上午走的进来. It is obligatory - it is the piece that actually marks the construction. Drop 是 and the sentence still works; drop 的 and it collapses.
Step 3 - Position 的 when there is an object. With a noun object you have two natural orders: 的 before the object (我是在上海学的中文, Wǒ shì zài Shànghǎi xué de Zhōngwén) or after it (我是在上海学中文的). But if the object is a pronoun, 的 must go at the very end, after the pronoun: 我是昨天认识他的 (Wǒ shì zuótiān rènshi tā de), never 认识的他.
Step 4 - Negate with 不是. To deny the focused circumstance, use 不是……的: 我不是昨天来的 (Wǒ bù shì zuótiān lái de, it wasn’t yesterday that I came). In the negative, 是 can never be dropped.
Step 5 - Drop 是 if you like (affirmative only). In a plain positive statement 是 is optional: 我昨天来的 = 我是昨天来的. Keep 是 in negatives and in questions.
Don’t confuse this focusing 是 with the plain equational 是 that links two nouns (A 是 B), owned by The verb 是 (A 是 B); and the completion 了 that simply reports an event happened is owned by Completed-action 了 (verb + 了).
Forms & patterns
What 是……的 can focus, and where 是 lands:
| Focus | Pattern | Example |
|---|---|---|
| Time (when) | S + 是 + time + V + 的 | 我是昨天来的 (Wǒ shì zuótiān lái de) - I came yesterday |
| Place (where) | S + 是 + 在 + place + V + 的 | 我是在北京出生的 (Wǒ shì zài Běijīng chūshēng de) - I was born in Beijing |
| Manner (how) | S + 是 + means + V + 的 | 他是坐飞机来的 (Tā shì zuò fēijī lái de) - he came by plane |
| Agent (who) | S + 是 + doer + V + 的 | 这是他做的 (Zhè shì tā zuò de) - he’s the one who made this |
Where 的 goes, by object type:
| Object | Order | Example |
|---|---|---|
| None | … V + 的 | 我是走着来的 (Wǒ shì zǒuzhe lái de) - I came on foot |
| Noun | … V + 的 + O or V + O + 的 | 我是在上海学的中文 / 我是在上海学中文的 |
| Pronoun | … V + pronoun + 的 (的 at the end) | 我是在学校认识他的 (Wǒ shì zài xuéxiào rènshi tā de) |
Statement, negative and question:
| Type | Form | Example |
|---|---|---|
| Affirmative | (是) … 的 | 我(是)昨天来的 (Wǒ (shì) zuótiān lái de) |
| Negative | 不是 … 的 | 我不是昨天来的 (Wǒ bù shì zuótiān lái de) |
| Yes/no question | 是不是 … 的 | 你是不是昨天来的？(Nǐ shì bu shì zuótiān lái de?) |
| Content question | 是 + question word … 的 | 你是什么时候来的？(Nǐ shì shénme shíhou lái de?) |
Examples
- 我是昨天来的。 (Wǒ shì zuótiān lái de.) - I came yesterday.
- 他是坐飞机来的。 (Tā shì zuò fēijī lái de.) - He came by plane.
- 我是在北京出生的。 (Wǒ shì zài Běijīng chūshēng de.) - I was born in Beijing.
- 这本书是谁写的？ (Zhè běn shū shì shéi xiě de?) - Who wrote this book?
- 你是什么时候到的？ (Nǐ shì shénme shíhou dào de?) - When did you arrive?
- 你是怎么知道的？ (Nǐ shì zěnme zhīdào de?) - How did you find out?
- 我是跟朋友去的。 (Wǒ shì gēn péngyou qù de.) - I went with friends.
- 我不是昨天来的，是今天来的。 (Wǒ bù shì zuótiān lái de, shì jīntiān lái de.) - I didn’t come yesterday, I came today.
- 我是在上海学的中文。 (Wǒ shì zài Shànghǎi xué de Zhōngwén.) - I studied Chinese in Shanghai.
- 火车票是我买的。 (Huǒchē piào shì wǒ mǎi de.) - I’m the one who bought the train tickets.
Common mistakes
- 我是昨天来。 -> 我是昨天来的。 (Wǒ shì zuótiān lái de.) - 的 is obligatory; it is what actually marks the focus construction, so a sentence with 是 but no 的 is incomplete.
- 你什么时候来了？ -> 你是什么时候来的？ (Nǐ shì shénme shíhou lái de?) - to ask when/how/where a known past action happened, use 是……的; 了 only reports that it happened, it can’t focus a circumstance.
- 我不昨天来的。 -> 我不是昨天来的。 (Wǒ bù shì zuótiān lái de.) - in the negative, 是 can never be dropped; you negate the focus with 不是.
- 我是昨天认识的他。 -> 我是昨天认识他的。 (Wǒ shì zuótiān rènshi tā de.) - when the object is a pronoun (他/她/它), 的 must sit at the very end, after the pronoun - never between the verb and a pronoun object.
- 我昨天是来的。 -> 我是昨天来的。 (Wǒ shì zuótiān lái de.) - 是 goes directly before the element you are spotlighting (here 昨天), not in front of the verb.
Tips
- The litmus test versus 了: is the event itself the news, or is it already accepted as done and you’re pinning down a detail? News -> 了 (我买了一辆车, Wǒ mǎi le yī liàng chē, I bought a car). A detail of a known event -> 是……的 (我是去年买的, Wǒ shì qùnián mǎi de, it was last year that I bought it).
- 是 is droppable, 的 is not. In plain affirmatives you can leave out 是 (我昨天来的 = 我是昨天来的), but 的 is the heart of the construction and can never go. Keep 是 whenever you negate or ask a question.
- 是……的 almost always looks backward at completed events. It is the natural, everyday way to interrogate their circumstances - “When did you…? How did you…? Where did you…?” all come out as 是……的 in real Chinese.
- Pronunciation: 不 is written bù but is said bú before a fourth tone, so 不是 comes out as bú shì. Likewise 一 is written yī but shifts to yí before a fourth tone, as in yí liàng (一辆).